Short-circuiting and brush-lifting device for dynamo-electric machines



C. B. MILLS SHORT CIRCUITING AND BRUSH LIFTING DEVICE FOR DYNAMO ELECTRIC MACHINES.

APPLICATION FILED APR- 9, 1918- Patented Sept. 27, 1921.

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ATrBRNEY To all whom it may concern:

UN TE STA E CHESTER B. "MILLS, or nas'r MoKnEsron'r, M

' nousnnmio'rmc AND manuracrumno COMPANY, A oonronnrron or PENN SYLVANIA.

PATENT OFFICE.

PENNSYLVANIA, ASSIGNOR TO WESTING- 1,392,193. p Application filed A ne,

Be it known that I, Gi-InsTnR'B. Mints, a

citizen of the United States, and a resident of East McKeesport, in the county of'Allegheny and State of Pennsylvania, have invented a new and useful] Improvement in Short-Circuiting and Brush-Lifting Devices for Dynamo-Electric Machines,of which the following isa specification. A

My invention relates to shortcircuiting devices for dynamo electric machinesthat are particularly adapted for use in connection with current-collecting 1 rings of 'induo tion motors of the wound-rotor type. 1

The object of myinvention'is to produce a simple, compact and durable means whereby the'collector rings may be short-circuited and the current-collecting devices raised by successive movements ofal single handle.

- Heretofore, it hasbeen customary to accomplish the aforementioned results, either by means of a single device, which must necessarily be comphcatedand therefore expensive, or by means of two independent devices"which,being' separate, occupy much needed space within the machine casing and usually require aspeciallydesigned casins therefor. 4 I

Bymy invention, I provide a'devicewhich occupies a minimumamount' of space and which may be mounted on "a standard machine without any material modification of the'oasing'. f i

Referring more particularly to the drawing, Figure 1 is a" longitudinal. sectional view of a portion of a dynamo-electric machine embodying my invention and Fig.

of the de- 2is a'trans' verse sectional view vice illustrated in Fig. 1. r

Referringmore particularly to the drawing,--I, have shown a dynamo-electric ma chine l'providediwith astator 2 and'a rotor 3 which is mounted upon a shaft 4 and is electrically connected to collector rings 5 which are mounted upon an insulating supporting ring 8, which, in turn, is mounted upon the shaft 4. Current-collecting devices 6 bear upon each of the collector rings 5. Each of the collector rings 5 is provided with a contact member 7 which is electrically connected thereto and which projects from one end of the insulating supporting ring 8 upon which the collectorrings are mounted. The contacts 7 are adapted to be short-cir- Specification of Letters Patent.

snonnomcurrlive AND BR sn-Lir'rme DEVICEFORDYNAMO-ELECTRIC MACHINES.

Patented Sept. 27, 1921. 191's. Serial N 227,416.

cuited by contact clips 9 mounted :upon a movable short-circuiting ring 10. The shortcircuiting ring 10 is provided with a groove 11 on its external periphery within which a yoke member 12 is adapted to ride and by means of which the short-circuiting ring is moved'into and' out of engagement with the contact members 7. The yoke member 12 is mounted upona shaft 13 which is provided with bearings l t and is operated by means of ahandle 15 which is located outside of the machine casing.

A gear wheel 16 is also mounted upon the shaft 13 and cooperates with an annular supporting member 17 upon which members 18, having cam-shape surfaces, are mounted to raise the brushes 6, as best shown in Fig. 2. When the supporting member 17 is subjected to rotative movement, the cam-shape faces of members 18 are moved into engagement with pins 19, which project from the currentcollectingdevices 6, to move them out of engagement with the collector rings 5. The members 18 are also provided, at their outer edges, with notches 20 within which the p ns 19 rest during-the time that the machine is operated with'thebrushes raised.

, The shaft 131s provided also with a locking device 21' mountedon one of, the bearings 14 which prevents. the shaft from being rotated to'raisethe brushes until the collectorgrings have. been short-circuited. The locking 'dev ce 2lcomprises a pin 22 mounted on the shaft'lS' on the open side of one of the bearthereof. The pins are spacedapart a distance greater than the width of the bearing. bearing is provided with a narrow slot 24 in which the pin 22 rests when the colflector rin'gs are not short-circuited and in which position the shaft 13' cannot be ro- 'tated, thus preventing the brushes from be- 'ings 14:" and a pin 23 on the machine side i from the machine, thereby moving the clips 9 of the short-circuiting ring 10 into engagement with the contact pins 7 which'are circumferentially disposed upon the supporting ring 8. The handle 15 is then turned to cause the gear wheel 16 to rotate the member "17 upon which the members 18 are mounted, whereby the cam faces of'the latter engage the pins 19 to lift the brushes from the collector rings. A further movement of the handle 15 rotates the ring 17 still farther to cause the pins 19 to engage the notches 20, where they remain during normal operation of the machine.

From the foregoing description, it will be readily appa'rentto those skilled in the art that the specified operations are performed by two independent and simple movements of the same handle and that there is no possibility of making any mistake in starting the machine, since the locking device prevents any movement of the handle 15 other than the'correct one.

lVhile I have shown a preferred form of my invention, it will be obvious to those skilled in the art that it is not so limited but is susceptible of various minor changes and modifications Within the scope of the appended claims.

I claim as my invention:

1. In a dynamo-electric machine, the combination with a plurality of collector rings, and current-collecting devices in engagement therewith, each of said devices being provided with a projection, of a semiannular ringmember provided with a camshape surface mounted adjacent each of said devices so as to engage said projection, all of said ring members being connected into a unitary structure, and means for rotating said structure.

2., In a dynamo-electric machine, the combination with aplurality of collector rings, and currentcollecting devices in engagement therewith, each of said devices being provided witha projection, of a semi-annular ring member provided with a camshape surface mounted adjacent such of said devices so as to engage said projection, said cam-shape surface beingprovided with a notch at the highest point thereof for the reception of said projection, all of said ring members being connected into a unitary with a cam-shape surface for engaging the supporting structure of one of said ourrent-collecting devices, said members being mounted on a supporting member which is adapted for rotatlve movement.

4. In a'dynamo-elec'tric machine, the combination with a plurality of collector rings and current-collecting devices in engagement therewith, each of said devices being provided with a projection, of a ring member adapted to short circuit said collector rings when subjected to longitudinal movement, and a shaft provided with an arm which is adapted to coact with said short-circuiting ring to move said ring in a longitudinal direction, and a device for moving said current-collecting devices out of engagement with said collector rings comprising members mounted on an annular supporting member and provided with cam-shape surfaces which are adapted to engage the said projection on the said current-collecting devices when said supporting member is subjected to rotative movement, and with a gear wheel mounted on said shaft and adapted to coact with said annular supporting member to produce a rotative movement thereof.

In testimony whereof, I have hereunto subscribed my name this 30th day of March, 1918.

CHESTER B. MILLS.

It is hereby certified that in Letters Patent No. 1,392,193, granted September 27, 1921, upon the application of Chester B. Mills, of East McKeesport, Pennsylvania, for an improvement in Shortlircuiting and Brush-Lifting Devices for Dynamo- Electric Machines, an error appears in the printed specification requiring correction as follows: Page 2, line 54, claim 2, for the Word such read each; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Ofiice.

Signed and sealed this 29th day of November, A. D 1921.

SEAL KARL FENNING,

Acting Commissioner of Patentsl It is hereby certified that in Letters Patent N 0. 1,392,193, granted September 27, 1921, upon the application of Chester B. Mills, of East McKeesport, Pennsylvania, for an improvement in Short- Tircuiting and Brush-Lifting Devices for Dynamo- Electric Machines, an error appears in the printed specification requiring correction as follows: Page 2, line 54, claim 2, for the Word such read each; and that the said Letters Patent should be read with this correctiontherein that the same may conform to the record of the case in the Patent Ofiice.

Signed and scaled this 29th day of November, A. D., 1921.

SEAL KARL FENNING,

Acting Commissioner of Pa tentsl 

